Iran's supreme leader has said Saudi Arabia's alignment with the United States and Israel is "certainly a betrayal" of the Muslims.

Ayatollah Ali Khamenei made the remark at a conference attended by parliamentary representatives from Islamic countries on Tuesday in Tehran, according to a statement published on his official website.

Discussing the recent US recognition of Jerusalem as the capital of Israel, he said the Holy City was “undoubtedly” the capital of Palestine, adding that Washington’s move “won’t bear results”.

According to the statement, Khamenei also accused Saudi Arabia of helping the US and the “Zionists”.

“This is certainly a betrayal of the Islamic Ummah and the Muslim World,” he said.

In another part of his speech, he said: “We’re ready to act brotherly even with those among the Muslims who were once openly hostile to Iran.

“The world of Islam, with such a large population and plenty of facilities, can certainly create a great power within the world and become influential through unity.

“Such warmongering among the world of Islam must be stopped and we should not allow that a safe haven be created for the Zionist regime.” Aljazeera wrote.